Designing Programs for Eliminating Canine Rabies from Islands: Bali, Indonesia as a Case Study

Abstract

BackgroundCanine rabies is one of the most important and feared zoonotic diseases in the world. In some regions rabies elimination is being successfully coordinated, whereas in others rabies is endemic and continues to spread to uninfected areas. As epidemics emerge, both accepted and contentious control methods are used, as questions remain over the most effective strategy to eliminate rabies. The Indonesian island of Bali was rabies-free until 2008 when an epidemic in domestic dogs began, resulting in the deaths of over 100 people. Here we analyze data from the epidemic and compare the effectiveness of control methods at eliminating rabies.Methodology/Principal FindingsUsing data from Bali, we estimated the basic reproductive number, R 0, of rabies in dogs, to be ∼1·2, almost identical to that obtained in ten–fold less dense dog populations and suggesting rabies will not be effectively controlled by reducing dog density. We then developed a model to compare options for mass dog vaccination. Comprehensive high coverage was the single most important factor for achieving elimination, with omission of even small areas (<0.5% of the dog population) jeopardizing success. Parameterizing the model with data from the 2010 and 2011 vaccination campaigns, we show that a comprehensive high coverage campaign in 2012 would likely result in elimination, saving ∼550 human lives and ∼$15 million in prophylaxis costs over the next ten years.Conclusions/SignificanceThe elimination of rabies from Bali will not be achieved through achievable reductions in dog density. To ensure elimination, concerted high coverage, repeated, mass dog vaccination campaigns are necessary and the cooperation of all regions of the island is critical. Momentum is building towards development of a strategy for the global elimination of canine rabies, and this study offers valuable new insights about the dynamics and control of this disease, with immediate practical relevance.

Estimating Burdens of Neglected Tropical Zoonotic Diseases on Islands with Introduced Mammals

“…61 Management of introduced mammals on inhabited islands implies social, cultural, and economic challenges that should be considered when assessing the feasibility of management actions. 58,62,63 For example, costs of eradication vary greatly, mostly as a function of population size, island area (e.g., US $3 to $20,000 per hectare), the type of eradication method (target species dependent), and other variable costs such as capacity building, environmental compliance, and mitigation of nontarget species. 20,57,58 Incorporating disease burden estimates into feasibility assessments for introduced mammal eradications can potentially expand the rationale and utility of these actions.…”

Ecology and Demography of Free-Roaming Domestic Dogs in Rural Villages near Serengeti National Park in Tanzania

“…These concerns for public and wildlife health have led to mass domestic dog vaccination programs in many developing countries including Tanzania. Although such programs have been effective in eliminating rabies outbreaks in domestic dogs [25–28], understanding the demography of the targeted domestic dog populations will be key to future success. Such knowledge can influence logistics such as the quantity of vaccines required and the frequency of vaccination campaigns.…”

Implementing Pasteur's vision for rabies elimination

“…Empirical and theoretical studies of mass dog vaccination campaigns in low-income countries reveal that vaccinating dogs against rabies is cost-effective up to the critical 70% vaccination coverage threshold ( Fig. 1) (9), is significantly less expensive over the long-term than providing PEP to bite victims, and can result in substantial savings to the public health sector (8,9,18). These savings will be particularly relevant in Asia where currently 90% of global PEP is administered (2, 3).…”